The present invention relates to air conditioning units and in particular to a means for assisting in the cooling of the air conditioner's condenser coils.
The conventional central air conditioning system used for residential dwellings typically includes evaporation coils, condenser coils, a compressor, and a fan which directs an air flow across the condenser coils. Passing a stream of air across the condenser coils cools the coils as well as the refrigerant flowing therethrough. Generally, these elements of the air conditioning system are found in an outside compressor unit although, in some instances, the evaporation coils are not found in the compressor unit but, instead, with a plenum which is a part of the dwelling's ductwork.
In the mechanical refrigeration cycle of a conventional central air conditioning system, a liquid refrigerant is contained initially in a receiver, which is usually located in the lower section of the condenser coils, although it can be contained within a separate tank. The compressor, acting as a pump, forces the liquid refrigerant under high pressure through a conduit to an expansion device.
The function of the expansion device is to regulate the flow of refrigerant into the evaporation coils. This expansion device may be in the form of an expansion valve or a capillary tube.
As the high pressure liquid refrigerant is forced through the expansion device, it expands to a large volume in the evaporation coils, thus reducing its pressure and consequently its boiling temperature. Under this low pressure, the liquid refrigerant boils until it becomes a vapor. During this change of state, the refrigerant absorbs heat from the warm air, i.e., the air within the dwelling, flowing across the outside surfaces of the evaporation coils.
After the refrigerant has boiled or vaporized, thus removing a quota of heat, it is of no more value to the evaporation coils and must be removed to make way for more liquid refrigerant. Instead of being exhausted to the outdoor air, the low pressure heat laden refrigerant vapor is pumped out of the evaporation coils through a conduit to the compressor. The compressor then compresses the refrigerant vapor, increasing its temperature and pressure, and forces it along to the condenser coils.
At the condenser coils, the refrigerant vapor is cooled by lower temperature air passing over the condenser coils, thus absorbing some of the refrigerant heat. As a result, the air temperature increases and the refrigerant temperature decreases until the refrigerant is cooled to saturation condition. At this condition, the vapor will condense to a liquid. The liquid, still under high pressure, flows to the expansion device, thus completing the cycle.
With an energy crisis facing our nation and the world, the efficient use of energy consuming devices is most critical. In the field of air conditioners, and in particular refrigerant charged air conditioners, attempts have been made to reduce the cost of operating such systems by increasing their efficiency.
One manner of improving the cooling efficiency of a central air conditioning compression unit has been to spray a mist of cooling water across the condenser coils, as disclosed in U.S. Pat. No. 3,872,684 to Scott and U.S. Pat. No. 4,028,906 to Gingold et al.
In the Gingold et al apparatus, a mist or fog of water emanates from a nozzle and into the upstream side of the stream of air passing over the condenser coils. The water sprayed onto the condenser coils is a mixture of tap water and a solvent or detergent additive so as to prevent the formation of mineral deposits and other accumulations on the condenser coils. An accumulation of minerals and other deposits would decrease the cooling capacity of the condenser coils.
As for the Scott patent, it discloses the attachment of a radially fluted annular ring to the blower fan blades outer periphery. The annular ring is rotated through a water reservoir at a lower elevation in the compressor unit to thereby cause the water to be vaporized and directed into an air stream passing over the condenser coils.
In both the Gingold et al and Scott cooling systems, the cooling mist is delivered to the condensing coils only upon the operation of the compressor.
It is an object of the present invention to improve upon the cooling systems of air cooled air conditioning condenser coils which have been used in the past.
Another object of the present invention is to provide means for mixing, in appropriate proportions, the condensate from the runoff of the evaporation coils with tap water, and to supply such mixture in the form of a spray or fog across the condenser coils.
Yet a further object of the present invention is to provide means for operating the cooling system for condenser coils independent of the operation of the central air conditioner's compressor or blower fan.
Another object of the present invention is to provide a kit which can be utilized to retrofit existing air conditioning units with the condenser coil cooling system of the present invention.
These and other objects of the present invention will become more apparent from the subsequent description.